Nine cadets have been taken to hospital following suspected drug use at a military training camp.
A police inquiry is under way into the incident at Altcar Training Camp in Hightown, Merseyside.
All those taken to hospital have since been released.
A spokeswoman said: "Merseyside Police can confirm that they have commenced an investigation at Altcar Training Camp after a number of young cadets became unwell overnight (Saturday) following a suspected drug-taking incident.
"The exact circumstances cannot be confirmed at this time, however nine young people have been examined at two local hospitals and since released.
"At this time, it is believed that no other cadets have been affected. Parents of other children who attended the camp this weekend and who have any concerns about the health of their children should seek appropriate medical advice."